Download Deep Thought Oceanography Questions from Ch. 22

Earth
Formation of the
Solar System
The Nebular
Hypothesis is the
most widely
accepted model
of the formation
of our solar
system.
Nebular
Hypothesis
About 4.6 bya
a great cloud
of gas and
dust was
rotating slowly
in space.
Forces of gravity
caused the cloud
to begin to shrink.
As the size of the
cloud shrank the
rotation increased.
90% of the
material rotating
in the cloud
began to gather
around the
center and this
compression of
material made
the interior so
hot that
hydrogen fusion
occurred.
The fusion
formed a star
(our sun).
The remaining
10% of material in
the cloud formed a
plate-like disk
which surrounded
the sun.
The mass and
material within the
disks formed solid
patches of ice and
rock – eventually
forming our
planets, which
orbit our sun.
(solar system)
Earth is the 3rd
planet from the
sun.
Approximately
71% of Earth is
covered with water
and 29% is
covered with dry
land.
Earth has 4 main layers:
•Inner Core
•Outer Core
•Mantle
•Crust
The Lithosphere is the crust and upper portion of
the mantle. (The more rigid material).
Lithosphere =
The Plates
The Asthenosphere is the lower mantle (partially
melted layer), and is responsible for the
movement of the Earth’s crust (plates – also
known as plate tectonics).
Asthenosphere =
What the plates
move on
Some of the heat that caused
Earth’s layers came from
meteor impacts over 4 billion
year ago, from decay of
radioactive isotopes
(elements releasing heat as
they disintegrate into more
stable forms), and from
weight of overlying materials
that caused compression in
Earth’s interior.
Now Earth is slowly losing heat because: some
rocks lose heat more quickly than others, the
thickness of the crustal rock varies from place to
place, and the percentage of radioactive materials
in rocks varies.
Earth’s Rotation
Earth is tilted on its axis about
23.5º and moves in a
counterclockwise direction.
(This gives the appearance the
sun rises in the east and sets in
the west).
Earth rotates (completes one
turn on its axis) 360º about
every 24 hours = our days and
nights.
In the Northern Hemisphere,
Earth’s axis points towards Polaris
(the North Star).
Evidence and effects of Earth’s
rotation are:
Foucault’s pendelum and the Coriolis Effect.
Evidence and effects of Earth’s
rotation are:
• Jean Foucault’s Pendelum –
(moving about 11º in a clockwise
direction each hour)
• The Coriolis Effect - (winds appear to turn
or be deflected to the right in the Northern
Hemisphere and to the left in the
Southern Hemisphere).
Earth’s Revolution
Earth rotates and revolves in a
counterclockwise direction.
Earth makes one revolution
(one orbit) around the sun every
365.24 days = about 1 year.
Evidence for Earth’s revolution was the
appearance that stars were shifting positions in the
sky.
This
appearance of
stars shifting
in the sky is
called
parallax.
The Earth’s orbit is an ellipse, or elliptical,
therefore, there are times when Earth is closer to
the sun and times when its further from the sun.
Periphelion is when Earth is closest to the sun.
Aphelion is when Earth is furthest from the sun.
Earth’s tilt causes the seasons on Earth.
Seasons and variations in the length of days and
nights are effects of the Earth’s revolution and tilt.
The hemisphere tilted towards the sun receives
more direct sunlight, so that hemisphere has
warmer temperatures and longer days.
(Therefore, the
hemisphere tilted away
from the sun receives
indirect sunlight, so
that hemisphere has
cooler temperatures
and shorter days).
The Summer Solstice is June 21st and it is the 1st
day of summer in the Northern Hemisphere
(N.Hemi at its maximum tilt towards sun).
Because we tilt 23.5º, the sun is straight overhead
at locations along the 23.5º N latitude line (Tropic
of Cancer). Areas above the 66.5º N latitude
(Arctic Circle) experience 24 hours of daylight.
This the Longest
Day of the Year.
The Winter Solstice is December 21st and it is the
shortest day of the year in the Northern
Hemisphere (N.Hemi at its maximum tilt away from
the sun). This is the Shortest Day of the year.
The Vernal Equinox is on March 21st
The Autumnal Equinox is on
September 22nd.
Day and night are equal in length all
over the world on these dates.
Sunlight falls directly on the equator
(so day and night are equal because
neither hemisphere tilts toward the
sun).
What do winds and ocean currents
and evidence for Earth’s rotation all
have in common???
Coriolis Effect Link
Apparent curving of moving
objects (ie- Water) due to the
Earth’s rotation
Surface Current Link
Controlled by three factors
Global winds
Coriolis Effect
Continental Deflections
Deep Thought Oceanography Questions from Ch. 22:
1.What elements make up a water molecule and how are they
arranged?
2.How much of Earth’s surface to oceans cover?
3.Why does ice float on top of water?
4.Why do people float in the Dead Sea?
5.Is there salt in icebergs?
6.What happens to the salt when water freezes?
Deep Thought Oceanography Questions from Ch. 22:
7. How does salt get into oceans?
8.Does seawater freeze at 32ºF (0ºC)?
9.Why are there different temperature zones in the oceans?
10.Name a few things that are found in deep ocean life?
11.Would ocean salinity be lower or greater in areas of
heavy rainfall and areas where large amounts of fresh water
enter the ocean?
Ocean Floor
http://www.earthscape.org/t2/meg01/meg01c.html#margin
Oceanography Questions from Ch. 24:
1.Currents flowing away from the warm equator carry
(A. warm B. cold) water, and currents flowing toward the
equator come from the poles and carry (A. warm B. cold)
water.
2.Gulf Stream carries warm water that originates and ends
where?
3.What is the primary cause of surface currents?
4.Why is Labrador Current hazardous to ships going from
Europe to North America?
Oceanography Questions from Ch. 24:
1.What causes tides?
2.What is a high tide?
3.What is a low tide?
4.How are spring and neap tides different from high and low
tides?
5.Why do tides occur 50 minutes later each day?
6.Draw the position of the sun, moon, and earth during a spring
and neap tides.